systemd Developer Lennart Poettering lennart@poettering.net systemd-backlight@.service 8 systemd-backlight@.service systemd-backlight Load and save the display backlight brightness at boot and shutdown systemd-backlight@.service /usr/lib/systemd/systemd-backlight systemd-backlight@.service is a service that restores the display backlight brightness at early boot and saves it at shutdown. On disk, the backlight brightness is stored in /var/lib/systemd/backlight/. During loading, if the udev property ID_BACKLIGHT_CLAMP is not set to false, the brightness is clamped to a value of at least 1 or 5% of maximum brightness, whichever is greater. This restriction will be removed when the kernel allows user space to reliably set a brightness value which does not turn off the display. systemd-backlight understands the following kernel command line parameter: systemd.restore_state= Takes a boolean argument. Defaults to 1. If 0, does not restore the backlight settings on boot. However, settings will still be stored on shutdown. systemd1